How can I fix the error with imap?

Question

Python

I have code:

import imaplib, email, os

def code_from_email(user, password):
  imap_url = "imap.mail.yahoo.com"
  connection = imaplib.IMAP4_SSL(imap_url)
  connection.login(user, password)
  connection.select("INBOX")
  start_message_uid = 1100
  result, data = connection.uid('search', None, "FROM", '[email protected]')
  code = ''
  while code == '':
    if result == 'OK':
      for num in data[-1].split():
        result, data = connection.uid('fetch', num, '(RFC822)')
        if result == 'OK':
          email_message = email.message_from_bytes(data[0][1])
          code = str(email_message.get_payload()[1])
  connection.close()
  connection.logout()
  return code   

f = open('emails.txt', 'r')
for line in f.readlines():
  user = line.split(':')[0]
  password = line.split(':')[1]
  print(user, password)
  code  = code_from_email(user, password)

The essence of the code - we read from the file all the logins and passwords of the mails, then we read the contents of the letter of the desired sender.
The problem is that when we pass 2 variables to the function, we get an error in response

File "C:\Users\User\AppData\Local\Programs\Python\Python39\lib\imaplib.py", line 610, in login
    typ, dat = self._simple_command('LOGIN', user, self._quote(password))
  File "C:\Users\User\AppData\Local\Programs\Python\Python39\lib\imaplib.py", line 1230, in _simple_command
    return self._command_complete(name, self._command(name, *args))
  File "C:\Users\User\AppData\Local\Programs\Python\Python39\lib\imaplib.py", line 1055, in _command_complete
    raise self.error('%s command error: %s %s' % (name, typ, data))
imaplib.error: LOGIN command error: BAD [b'[CLIENTBUG] LOGIN Command arguments invalid']

If we replace 2 variables with 2 strings

code  = code_from_email('[email protected]', '12345678')

Then there will be no error and we successfully read the letter.
Please tell me what this error can be connected with and how to solve it